require 'chef_fs/knife'
require 'chef_fs/file_system'
require 'chef/run_list'

class Chef
  class Knife
    remove_const(:Deps) if const_defined?(:Deps) && Deps.name == 'Chef::Knife::Deps' # override Chef's version
    class Deps < ::ChefFS::Knife
      ChefFS = ::ChefFS
      banner "knife deps PATTERN1 [PATTERNn]"

      common_options

      option :recurse,
        :long => '--[no-]recurse',
        :boolean => true,
        :description => "List dependencies recursively (default: true).  Only works with --tree."
      option :tree,
        :long => '--tree',
        :boolean => true,
        :description => "Show dependencies in a visual tree.  May show duplicates."
      option :remote,
        :long => '--remote',
        :boolean => true,
        :description => "List dependencies on the server instead of the local filesystem"

      attr_accessor :exit_code

      def run
        if config[:recurse] == false && !config[:tree]
          ui.error "--no-recurse requires --tree"
          exit(1)
        end
        config[:recurse] = true if config[:recurse].nil?

        @root = config[:remote] ? chef_fs : local_fs
        dependencies = {}
        pattern_args.each do |pattern|
          ChefFS::FileSystem.list(@root, pattern).each do |entry|
            if config[:tree]
              print_dependencies_tree(entry, dependencies)
            else
              print_flattened_dependencies(entry, dependencies)
            end
          end
        end
        exit exit_code if exit_code
      end

      def print_flattened_dependencies(entry, dependencies)
        if !dependencies[entry.path]
          dependencies[entry.path] = get_dependencies(entry)
          dependencies[entry.path].each do |child|
            child_entry = ChefFS::FileSystem.resolve_path(@root, child)
            print_flattened_dependencies(child_entry, dependencies)
          end
          output format_path(entry)
        end
      end

      def print_dependencies_tree(entry, dependencies, printed = {}, depth = 0)
        dependencies[entry.path] = get_dependencies(entry) if !dependencies[entry.path]
        output "#{'  '*depth}#{format_path(entry)}"
        if !printed[entry.path] && (config[:recurse] || depth == 0)
          printed[entry.path] = true
          dependencies[entry.path].each do |child|
            child_entry = ChefFS::FileSystem.resolve_path(@root, child)
            print_dependencies_tree(child_entry, dependencies, printed, depth+1)
          end
        end
      end

      def get_dependencies(entry)
        begin
          if entry.parent && entry.parent.path == '/cookbooks'
            return entry.chef_object.metadata.dependencies.keys.map { |cookbook| "/cookbooks/#{cookbook}" }

          elsif entry.parent && entry.parent.path == '/nodes'
            node = JSON.parse(entry.read, :create_additions => false)
            result = []
            if node['chef_environment'] && node['chef_environment'] != '_default'
              result << "/environments/#{node['chef_environment']}.json"
            end
            if node['run_list']
              result += dependencies_from_runlist(node['run_list'])
            end
            result

          elsif entry.parent && entry.parent.path == '/roles'
            role = JSON.parse(entry.read, :create_additions => false)
            result = []
            if role['run_list']
              dependencies_from_runlist(role['run_list']).each do |dependency|
                result << dependency if !result.include?(dependency)
              end
            end
            if role['env_run_lists']
              role['env_run_lists'].each_pair do |env,run_list|
                dependencies_from_runlist(run_list).each do |dependency|
                  result << dependency if !result.include?(dependency)
                end
              end
            end
            result

          elsif !entry.exists?
            raise ChefFS::FileSystem::NotFoundError.new(entry)

          else
            []
          end
        rescue ChefFS::FileSystem::NotFoundError => e
          ui.error "#{format_path(e.entry)}: No such file or directory"
          self.exit_code = 2
          []
        end
      end

      def dependencies_from_runlist(run_list)
        chef_run_list = Chef::RunList.new
        chef_run_list.reset!(run_list)
        chef_run_list.map do |run_list_item|
          case run_list_item.type
          when :role
            "/roles/#{run_list_item.name}.json"
          when :recipe
            if run_list_item.name =~ /(.+)::[^:]*/
              "/cookbooks/#{$1}"
            else
              "/cookbooks/#{run_list_item.name}"
            end
          else
            raise "Unknown run list item type #{run_list_item.type}"
          end
        end
      end
    end
  end
end